The progress of scaling of LSIs has led to finer and finer circuit line widths of semiconductor devices. An approach employed to form desired circuit patterns on semiconductor devices uses a step-and-repeat exposure system to demagnify and transfer, onto a wafer, a high-precision master pattern (also called a mask, or a reticle particularly when used in a stepper or scanner) formed on a piece of quartz. The high-precision original pattern is written with an electron beam writing apparatus by use of a so-called electron beam lithography technique.
An exemplary known electron-beam writing apparatus is a multibeam writing apparatus in which a multibeam is used to emit many beams at a time for improvement in throughput. In this multibeam writing apparatus, for example, an electron beam emitted from an electron gun passes through an aperture plate having multiple holes. Thus, multiple beams are formed, and each of the beams is subjected to blanking control by using a blanking aperture array. Beams that have not been deflected through the blanking control are demagnified by using an optical system, and exposing a blanks, which is a writing target, at a desired position.
Multiple holes are formed in a blanking aperture array. A pair of electrodes (blanker) is provided in a portion close to each of the holes. By applying a given voltage between the pair of electrodes, a beam is subjected to blanking deflection, and enters the beam OFF state.
Many blankers are provided on the blanking aperture array. The blankers may include a blanker that is not capable of applying a desired voltage between the electrodes. Such a blanker is not capable of entering the beam OFF state through control. A defective beam that is always in the beam ON state is produced. Therefore, a problem has arisen in that the writing accuracy is deteriorated.